Improvement in hammers for dressing stone



A. MoDONALD. Hammer for Dressing Stone. N0. I97,283.

Patented Nov. 20, I877.

b nemre-r.

WISHINGTON D G N PETERS. PH

UNITE STATES PATENT OFFICE.

ALEXANDER MCDONALD, OF BELMONT, MASSACHUSETTS.

IMPROVEMENT IN HAMMERS FOR DRESSING STONE.

Specification forming part of Letters Patent No. 197,283, dated November 20, 1877 application filed October 24, 1877.

To all whom it may concern:

Be it known that I, ALEXANDER McDoN- ALD, of Belmont, of the county of Middlesex and State of Massachusetts, have invented a new and useful Improvement in Hammers for Dressing Stone; and-do hereby declare the same to be described in the following specification and represented in the accompanying drawings, of which- Figure 1 is a top view, Fig. 2 a side elevation, and Fig. 3 a longitudinal section, of a hammer-head provided with my invention.

In some respects the said hammer-head is like those described and represented in the United States PatentsNos.153,950 and185,999, though differing therefrom in other and important particulars.

The head is recessed to receive a series of cutters, and it is wedge-shaped or tapering, and provided with a collar to encompass and clamp its two parts together and upon the set of cutters.

The two parts of the body are shown at A and B, the collar at O, and the series of cutters at D.

The said jawed parts A B are not united in rear, or in one piece of metal, but they are in separate pieces, and each is recessed to receive the chisels and handle.

The rear end of the lesser part or clamp B is oblique to, or makes an acute angle with, the inner face of the clamp, and when in place it rests against a shoulder or abutment, a, formed in the other part, and correspondingly oblique to, or inclined to, the inner face of the part A, all being as shown. Furthermore, the said part B has a rib, b, curved or semicircular in shape, in transverse section, projecting from it at its rear end, and entering a corresponding groove, 0, formed in the part A. The said rib and groove extend from top to bottom of the head, and are to prevent the clamp portion B from being, driven down on the part A while the hammer may be in use.

When screws are employed, in manner as shown in the Patent 153,950, to confine the clamp-plate to the rest of the hammer-head,

they are liable to be cut or broken off by the momentum of the clamp-plate while the head may be 'in use. The rib b and groove 0 enable such screws to be dispensed with when the clamp-plate and rest of the head are in separate pieces.

It is very desirable not only to have the said clamp B separate from the rest of the head, but to have it held thereto and to the cutters by a collar, for by having the clamp plate or part B removable from the part A the cutters and handle can be detached from or be applied to the head with greater facility.

In order to prevent the handle from working loose in its socket e in the head, or, while being driven into such socket, from pressing the clamp part B away from the part A, the latter is provided with the oblique shoulder a, and the former, or part B, is constructed with the oblique end to rest against such shoulder, all being as represented.

I would remark that I do not herein claim a stone-dressing hammer constructed as represented in either of the aforesaid Patents Nos. 153,950 and 185,999; but

I'claim as my invention or improvement in the bush or stone-dressing hammer as follows, V1Z:

1. The tapered and separate head parts A and B, provided with the rib b and groove 0, arranged as set forth.

2. The tapered and separate head parts A and B, provided with the rib b, groove 0, and collar 0, arranged as set forth.

3. The tapered and separate head parts A and B, provided with the rib b, groove 0, oblique shoulder a, and handle-socket 0, arranged as represented.

4. The tapered and separate parts A and B, provided with the collar 0, the rib b, groove 0, handlesocket c, and oblique shoulder a, arranged as set forth.

ALEXR. MCDONALD. 

